Condenser tube cleaner



March 9, 1943. g T. J..BAY

- CONDENSER TUBE CLEANER Filed Aug. 26, 1942 ing steam in contact herentprotective coating Patented Mar. 9, 1943 ThomasY J. Bay, United StatesNavy VAppncation August 2c, 1942, serial No. 456,215

3 Claims:

(Granted under the act of amended April 30, 1928;

The present invention relates to tube and pipe cleaners and it hasaparticular relation to cleaners for the Water cooled tubes of steamsurface condensers.

Deposits of slime and otherv foreign matter on the inside surfaces ofsteam condenser tubes tend to decrease the flow of heat from thecondenswith the outside of the tubes, through the metallic tube Wall, tothe cooling watr flowing through the tubes. Thus the effectiveness ofthe condenser is gradually decreased and it becomes necessary to cleanthe inner surfaces of the tubes periodically in order to maintainreasonably high vacuum consistent with satisfactory and eicientoperation of steam turbines and other apparatus served by the condensingequipment.

In tropical Waters slime formation on condenser tube surfaces is muchmore rapid than in'colder waters and the relatively high temperature ofthe circulating Water has a direct effect in Areduction of the condenservacuum obtainable. High temperature. circulating water combined withhigh power operation of propelling machinery tends to overloadcondensing equipment and reduce condenser vacuum below safe andeconomical limits unless the tube surfaces are kept free of slimecoatings and other deposits of foreign matter. A

Periodic removal of foreign deposits from the interior surfaces -ofnaval vessel condenser tubes has been required in the past principallyas -a measure for minimizing 4corrosion of the tubes and depositattackor selective pitting of the-metal tube surfaces underneathparticles of -foreign matter. The standard method ofvcleaning navalvessel condenser tubes has been by use of an air o'r water lance tosweep out foreign deposits. In cases of extreme fouling, as often occurin the tropics, rubber plugs have beenv employed for cleaningthe tubes.These rubber plugs are slightly larger than the inside diameter ofthetubes `and are forced through -the tubes by use of air or water pressureto scrape off the slime and other foreign matter. The use of rotatingmetallic wire brushes, Scrapers and other types of metallic condensertube cleaners of various ktypes for cleaning naval vessel condensertubes is prohibited because the metal scraping parts of these devicesscratch and otherwise'injure the interior surfaces of the tubes bydamaging the thin, ad-

and rendering the tubes subject to accelerated corrosion, pitting'andearly service failure.. i Y y The rubber plugcleaning method mentioned`into practical s ments in their March `1833, as 37o o. G. 757) abovehas been found satisfactory for removing slime from condenser tubesurfaces under certain applications. One of the principal objections tothe use Vof rubber. plugs at present is associated which arelnserted inthe inlet end of the condenser tubes to prevent corrosion and impingmenterosion. Such an assembly is shown in my patent. Under these conditionsit 1s extremely dicult to insert a rubber plug tube cleaner into cleanerof the rotary type which will -pass freely through the restricted throator neck portion of a condenserV tube protector and vvhich willthereafter expand into intimate contactwith the vvall of the tube inorder' to remove foreign matter therefrom.

Another object of the invention is the provision of a condenser tubecleaner provided with means for supplying. Water thereto for lubricatingthe same and for flushing the tube as. the cleaner removes deposits fromthe Wall thereof. Y

. A'further object ofthe inventionis the provision of a cleaner in whichthe water supplied thereto also functions to yieldably maintain theblades of the 'cleaner in contact; with the tube wall. Y

With these and other objects in view, as well as other advantagesthatmay be incident to the appended claims. Y K

In order togmake the invention more clearly understood, there areshown-iny the accompanying drawing, means'for carrying the inventionuse, vwithout limiting the improveuseful application to the particularconstructions,`which, for the purpose of extration. i

planation, have been made the/subject `of illusand erosion resisting itsinletend. This protector is formed with a pointed out, this the cleanerthrough a separate pipe extending parallel to the cleaner driveshaft;

Fig-5 is a longitudinal sectional View illustratlng a cleaner headprovided with straight cleaning blades having tube contacting edges ofrubber, plastic or other material softer than the condenser tube and inwhich the blades are held in contact with the tube wall by centrifugalaction;

Fig. 6 is a transverse sectionalview taken on line 5-6 of Fig. 5; and 1Fig. '1 isa transverse se tional View similar to Fig. 6, illustrating aconstruction in which held in contact With the of the water supplied tothe cleaning blades are tube wall bythe force the cleaner.

ReferringY to the drawing, and particularly to Fig. 1 thereof, acondenser tube cleaner embodying the present invention is shown ascomprising a body portion I provided with a plurality of spiral blades II of rubber or other suitable flexible material vulcanized thereto ormolded integrally therewith. The body rII) mayv also be constructed ofrubber but `it may be of metallic or plastic construction, if sodesired. The ilexible blades II of the cleaner contact rmly with theinner wall of a condenser tube I2` which is shown as being mounted in aheader plate I3 of a surface condenser and as having a corrosionprotector I4 mounted at restricted throat portion I5 for insuring thedesired waterY flow characteristics, as explained in my Reissue PatentVNo. 272,027. As previously throat portion of the protector has formed anobstruction for the passage of v cleaning devices previously employedbut the flexible rubber blades II ofthe present cleaner fold back as4the cleaner is inserted in the protector and 'pass therethroughwithlittle or no resistance.

The body I0 ofthe cleaner is shownas being vulcanized to a metallicnipple I6 Vwhich is threaded onto a male connecting memberl I1 securedto the end'of a exible driveshaft I8. This driveshaft may be rotated byany suitable means of commercial design such as an electric motorlocated ata remote point or a small hydraulically driven motor locatedadjacent to the cleaner head and passing through the condenser tubetogether with the cleaner.

Water is supplied to the cleaner through' a flexible pipe I9 whichVsurrounds the driveshaft I8 in spaced, relation thereto and whichterminates a short distance back 'of the cleaner head. A disk 20 ofrubber or other flexible material is. mounted on the end of the pipe I9and defines a water supply and distributing chamber 2l at the rear ofthe cleaner from which water ilows forwardly between the spiraljbla'de'sII of the cleaner. This disk 20 insures that the water delivered to thecleaner will flow forwardly through the tube Vand will not flowrearwardly therethrough around the pipe I9. The disk 20 operationperformed by the blades `cleaner may be rotated ina direction in whichlof the invention the forms a snug nt with the wall .of the condensertube I2 but is suiciently flexible to yield when passing through therestricted throat I5 of the protector VI4 when the cleaner is eitherinserted or withdrawn from the condenser tube. The disk also exerts ascouring action on the condenser tube wall following the major cleaningII.V The the spiral blades I I will tend to screw themselves forwardlyinto the slimy deposit on the tube wall or in an opposite direction inWhichthey will force the dislodged deposit forwardly, thus auginentingthe action of the flushing water. In either case the cleaner is rotatedrapidly enough to remove the .deposit from the condenser tube.

In Figs. 2 and 3 there is illustrated a construc- -tion in whichilushing water s supplied through a tubular` "driveshaft 22 whichcommunicates, through an axial passage 23 in the nipple I6, theconnector and body I0with radial passages 24 formed in Ythe :body I0 ofthe cleaner between the'blades rI I.

In Fig. 4 another construction is shown,wherein flushing water yissupplied to the water 4distributing chamber 2I through ,a separate pipe25 paralleling the piperaIS exteriorly thereto.

In Figs. `5 and 6 another Ifori-ri .of 'cleaner having collapsibleblades is shown. .In thisform of the invention the cleaner comprises ametallic body'portion 26 which is threaded into a connector v21 which isin turn threaded onto a tubu- -lar driveshaft 28. The body portion 26 isformed with a plurality of circumierentially spaced longitudinallyextending slots 29 in which cleaning blades 30 are .loosely mounted -for.radial movement into contact with the tube wall under centrifugalaction. These blades are maintained against displacement from the slots2'9 by means of caps 3l, one being permanently secured to the forwardend of the body portionZS and the other being` removably secured theretobetween the body portion 26 and the 'connector 21. The caps 3| overhangextensions or :tongue portions 32 formed on opposite .ends of the blades.30 and prevent them from becoming displaced, but at the Sametime permitof the vnecessary amount of radial movement.

The blades may be fabricated entirely from a suitable non-marringplastic material or may have, a metallic Vbase portion 33 edged with aplastic tube-,engaging portion 34.' Flushing water is supplied to jthecleaner between the blades from the tubular driveshaft 28 through anaxial passage 35 formed in the connector 21 and body portion 26 oflthevcleaner and radial passages 3S provided in the latter. In this formv blades of the cleaner are held in contact with the wall of the tube bycentrifugal action generated by the rapidly rotating cleaner.

In Fig. 7 there is shown a construction in which centrifugal actiontending to hold the blades of the cleaner in contact with the tube wallis augmented by the pressure of the water delivered to the cleaner. Thisis accomplished by arranging the radial passages so that they l willcommunicate'with the slots 29 beneath the blades 30, as indicated at 31.In this arrangement the Water delivered to the slots and tending to urgethe blades outwardly, will spray outwardly around the blades into theYcondenser tube for flushing purposes.

It will be understood that while the term "water has been employed inthe foregoing descriptlon, the invention contemplates the use of anysuitable uid such as air, steam or gas for dislodging and/or carryingaway the foreign matter. Also, it will be understood that in all of theembodiments of the invention, the blade elements are vconstructed from amaterial that is softer than the condenser tube, such as rubber,

plastic or other suitable material, so as to insure against scraping,scratching or otherwise marring the tube Wall during the cleaningoperation.

It will be understood that, as previously stated, the above descriptionand accompanying drawing comprehend only the general and preferredembodiment of the invention and that various changes in construction,proportion and arrangement of the parts may be made within the scope ofthe appended claims without sacrificing any of the advantages of theinvention.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the paymentof any royalties thereon or therefor.

What I claim is:

1. A tube cleaner comprising a rotatable shaft, a body portion securedto the end of said shaft for passage through a tube to be cleaned, ap1urality of blades of compressible material carried by said bodyportion for contact with the wall of said tube with a squeegee action toremove deposits of foreign matter therefrom, a flexible tubular membersurrounding said shaft, a flexible diaphragm fixed to the end of saidtubular member at the rear of and in spaced relation to said cleaner anddefining a fluid distributing chamber, said chamber being in fluidcommunication with a source of fluid under pressure for passage betweensaid blades to augment the cleaning action thereof and for carrying awayforeign matter dislodged from vthe wall of said tube by saidvblades.

2. A tube cleaner comprising a rotatable shaft, a body portion securedto the end of said shaft for passage through a tube to be cleaned, aplurality of blades of compressible material carried by said bodyportion for contact with the wall of said tube with a squeegee actionto' remove deposits of foreign matter therefrom, a flexible tubularmember surrounding said shaft, a flexible diaphragm fixed to the end ofsaid tubular member at the rear of and in spaced relation to saidcleaner and defining a uid distributing chamber, said chamber being influid communication through said tubularmember with a source of fluidunder pressure for passage between said blades to augment the cleaningaction thereof and for carrying away foreign matter dislodged from theWall of said tube by said blades.

3. A tube cleaner comprising a rotatable tubu, lar shaft, a body portionsecured to the end of A said shaft for passage through a tube to4 becleaned, a plurality of blades of compressible .material carried by saidbody portion for contact with the wall of said tube with a squeegeeaction to remove deposits of foreign matter therefrom, a flexibletubular member surrounding said shaft, a flexible diaphragm fixed to theend of said tubular member at the rear of and in spaced relation tosaid'cleaner and defining a fluiddistributing chamber, said chamberbeing in uid communication through said tubular shaft with a source offluid under pressure for passage between said blades to augment thecleaning action thereof and for carrying away foreign'matter dislodgedfrom the wall `of said tube by said blades THOMAS J. BAY.

